Drying-kiln



(No Model.) 2 Sheets-Shee`t 2. A.. T.,BEMIS. DRYING KILN.

,No.'ssla Patented Marl. 5, 1895.

NTTED STATES PATENT OFFICE.

ALBERT T. BEMIS, OF LOUISVILLE, KENTUCKY.

DRYING-KILN.

SIt"ECIFICATION forming part of Letters Patent No. 535,316, dated March 5, 1895.

Application tiled August 31| 1891.

To a/ZZ whom t may concern.-

Be it known that I, ALBERT T. Bui/trs, a citizen of the United States, residing at Louis ville, in the county of Jefferson and State of Kentucky, have invented certain new and useful Improvements in Drying-Kilns; and I do declare the following to be a full, clear, and exact descriptionof the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to the letters of reference marked thereon, which form a part of this specification.

This invention relates to certain new and useful improvements in dl'yingkilns; and it has for its object to provide means whereby a practically even temperature may be set up and maintained in thedryingchamber of a kiln of the class commonly known as progressive kilns, or that class of kilns in which the lumber, brick or other material to be dried is supplied to one end of the drying-chamber of the kiln, and during the process ot' drying passes to the opposite end of the kiln, where it is removed, while the new stock is being continuously supplied at the entrance ot' the kiln.

In this class of kilns various methods have been adopted for supplyingacontinuous current of heated air to the chamber of the kiln, such for instance as the air-blast, in which the current is maintained by means of an engine, fans, dac.; while in other instances the current has been maintained by means of stacks of sufficient height toinsure a uniform current. In still other instances it has been proposed to supply the requisite heat by arranging steam-pipes within a chamber beneath the ioor of the kiln, the heat being permitted to enter the drying-chamber through an inlet-passage provided in the iioor at one end of the kiln. With all of these systems of kiln drying, a serious objection has been Afound to exist, in the fact that the heated air depended upon for drying the lumber or other material, has had a tendency to rise to the upper portion of the chamber, and thus, while eftectually drying the material Within the upper portion of the chamber within a comparatively limited time, a much longer time has been required to completely dry the lower Serial No. 404,325. (No model.)

current of heated air admitted at one end of and passing longitudinally through the drying-chamber by heat radiated from a system of pipes arranged longitudinally ot' the chamber and located near the floor, the maximum of radiated heat being in the vicinity of the minimum of heat in the longitudinal current, and vice versa, I can produce and maintain an even temperature throughout the entire chamber.

The invention is fully illustrated in the accompanying drawings, which, with the letters of reference marked thereon, form. a part of this specification, like letters of reference indicating like parts throughout the several views, and in which- Figure l, is a central longitudinal vertical section through a drying-kiln provided with my improvement. Fig. 2, is a horizontal section of the same.

Reference now being had to the details of the drawings by letter, A designates a dryingkiln of ordinary construction. The heated air enters the drying-chamber through the airinlet passages B at one end, being heated by the heater C, and forced into the d rying-chamber by suitable fans D, and after traversing the length of the kiln it passes out through the outlet passage F at the other end of the chamber. This outlet passage F, is in the form of aconduit secured to and movable with the vertically movable door F', which has in its lower end an opening fcommunicating with the interior ot" the chamber, as seen in Fig. l.

G G represent tracks upon which the cars or trucks containing the lumber or other material travel, these tracks extending the entire length of the apartment.

Suitably supported upon racks H, a few inches above the floor of the chamber and between the tracks G, are steam-pipes I, arranged longitudinally of the dryingchamber which are supplied by either heat or steam from any suitable source through the inlet- ITO pipe I', located at that end of the steam-pipes most remote from the air-inlet end ot' the chamber. After traversing the system of pipes the exhaust steam or air escapes through the outlet-pipe l2, located near the air-inlet end of the chamber.

From the foregoing it will be observed that where the temperature of the air-eurrent is at its maximumit is intersected by the minimum of radiated heat, and Where the aircurrent is at its minimum temperature it is intersected by the maximum of radiated heat, and also that these relative conditions of temperature are maintained throughout the length of the floor-pipes, With the result that in ashort time after theheating of the chamberis commenced the temperature will be uniform in all parts of the drying-chamber.

It will be understood that the current of heated air may be passed longitudinally through the drying-chamber by means other than the fan. For instance, an air'tlue at the air-exit end of the kiln would cause the heated air to be drawn through the chamber.

Having thus described my invention,what I claim to be new, and desire to secure by Letters Patent, is-

l. As a means for producing an even teniperature Within drying-kilns, an air-heating apparatus, means for passing a current of heated air from said apparatus longitudinally through the-dryingfchamber, and a source of radiated heat within the chamber, near the door, and independent of said air-heating apparatus, which source, when the kiln is in operation, is hottest at that end of the chamber gitudinally through the drying chamber, the

air entering the chamber atl the end nearest the outlet of the pipe-system and discharging at the end nearest the inlet of said system.

3. In a kiln for drying lu mber and other like materials, a close-oored drying-chamber having one or more longitudinal car-tracks above the floor, a system of steam-pipes arranged longitudinallyof each track and slightlyabove vthe floor, the steam inlet and exhaust being at opposite ends of the chamber, an air-heater independent of the steam-pipes, and a fan for fo'rcinga current of air from said heater longitudinally through the drying-chamber, the air being admitted at the end nearest the steam-exhaust anddischarged at the end nearest the steam-inlet, substantially as described.

In testimony whereof I affix my signature in presence of two witnesses.

ALBERT T. BEMIS.

Witnesses:

FRANKLIN H. HOUGH, R. S. DONALDSON. 

